The Undone Slim Black - 4.9mm
$2951,899
37 mm30 m WRSapphire
The Sensei's take
The Undone Slim Black is perfect for those who appreciate ultra-thin design without sacrificing functionality. Its sleek profile and minimal aesthetics make it a versatile accessory for any occasion. With its limited availability and solid engineering, it’s a great value for those wanting something unique yet understated.
Is this watch your kind of thing?
One vote per visitor — see how the community feels.
Thinner than your phone. Sharper than ever. The UNDONE Slim 4.9mm Black Edition pushes minimal design into a more striking direction. At just 4.9mm , it stands among the thinnest watches in the microbrand space , refined into a full black case and bracelet, produced in limited quantities. For perspective: iPhone ≈ 7–8mm Pencil ≈ 6–7mm UNDONE Slim = 4.9mm Built with a 37mm stainless steel case and powered by a Swiss Ronda movement, it delivers precision in a form that feels almost invisible on the wrist. The dark finish adds depth and presence, while keeping the silhouette clean and understated. Minimal by design, it slips effortlessly under your cuff, never adding bulk, just a sleek, confident edge. Choose from Black, Blue, or Silver sunray dials, each shifting subtly with light against th…
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At a glance
Strengths & trade-offs
Pulled straight from the spec sheet, framed for the buyer. The editorial verdict is the Sensei's take above.
Strengths
- Scratch-resistant sapphire crystal
- Slim 4.9mm profile
- Versatile 37mm case
- Luminous dial and hands
Trade-offs
- Limited water resistance (30m)
- Priced above what the spec suggests
Sensei Says
The specs, in plain English
On the wrist
At 37 mm it lands in the modern sweet spot.
The value
Fairly priced for what it is.
On the wrist
How will this watch fit me?
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Wrist circumference
Preferred fit
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Specifications
- Reference
- SLM-BRC-004
- Released
- 2026
- Production
- Limited edition
- Case diameter
- 37 mm
- Thickness
- 4.9 mm
- Case shape
- Round
- Case material
- Stainless Steel
- Water resistance
- 30 m
- Crystal
- Sapphire
- Bezel
- None
- Caseback
- Closed
- Dial colour
- black
- Indices
- none
- Lume
- Yes — none
- Strap / bracelet
- integrated steel bracelet
- Fit
- Unisex
The maker
UNDONE
UNDONE believes that watches are more than mere timepieces; they are reflections of individuality and stories. The brand emphasizes the fusion of craftsmanship with user creativity, pushing the boundaries of traditional watch design.
Alternatives worth a look
Cheaper alternative
$95 less
Smaller alternative
3.0mm smaller
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